<!DOCTYPE html>
<html>

	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			.ul li:first-child {
				font-size: 20px;
				background:red;
			}
			.ul li:last-child {
				border: 1px solid #333;
			}
			.ul li:nth-child(2n) {
				background: yellow;
			}
		</style>
	</head>

	<body>
		<ul class="ul">
			<li>test1</li>
			<li>test2</li>
			<li>test3</li>
			<li>test4</li>
			<li>test5</li>
		</ul>

	</body>

</html>